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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 2 |
| 3 | 9 |
| 4 | 76 |
| 5 | 805 |
| 6 | 10626 |
| 7 | 167839 |
| 8 | 3091768 |
| 9 | 65127465 |
| 10 | 1544951350 |
| 11 | 40770052411 |
| 12 | 1184951084340 |
| 13 | 37616775522781 |
| 14 | 1295202587597842 |
| 15 | 48080003446006575 |
| 16 | 1914305438178286576 |
| 17 | 81379323738092982097 |
| 18 | 3679128029385789284718 |
| 19 | 176267238847686913800547 |
[1,0,2,9,76,805,10626,167839,3091768,65127465, 1544951350,40770052411,1184951084340, 37616775522781,1295202587597842,48080003446006575, 1914305438178286576,81379323738092982097, 3679128029385789284718,176267238847686913800547] |